New Mexico Pipe Fitter Journeyman (JPF) Practice Exam

Which type of check valve allows for immediate closure of the disk?

1. Vertical design check valve.

2. Outside lever and weight type check valve.

3. Spring-loaded check valve.

4. Ball check valve.

The correct answer is: Outside lever and weight type check valve.

The option indicating the outside lever and weight type check valve is notable for its capability of providing immediate closure of the disk. This type of valve uses a lever and a weight mechanism to enhance the closing action. When there is a reverse flow, the weight assists in quickly pushing the disk to its closed position, minimizing any potential backflow. This design is particularly advantageous in applications where sudden changes in pressure or flow rates might occur, as it ensures that the valve reacts swiftly to prevent any backflow that could compromise system integrity. The weight mechanism operates effectively under a variety of conditions, making it reliable for immediate response to reverse flow situations. In contrast, other types of check valves, while effective in their own right, do not possess the same immediacy in closure. The spring-loaded check valve relies on the tension of the spring to close the disk, which may not react as quickly to rapid changes in flow. Meanwhile, vertical design check valves and ball check valves operate based on different principles that may introduce delays in closure.